What you’ll learn in this Java tutorial In this article, you’ll learn what assertions are, how to write them, and how to use them in your Java programs: ...

Learn how to use synchronous and asynchronous callbacks in Java—including callbacks with lambda expressions, CompletableFuture, and more.

A method might accept a specific type and its subclasses, but you want to restrict usage to a select few implementations of your own design. Java's open inheritance model can feel like an open ...